JP2007156220A - Manufacturing method for display, display and electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method for a display which has improved manufacturing efficiency, and also to provide the display and electronic equipment. <P>SOLUTION: A column spacer 57 can be formed by using a bank film 71 forming banks B1 and B2, so that neither a new material nor a new step is needed and the manufacturing efficiency can be improved. The column spacer 67 can be formed in a region where a TFT element 30 is formed, different from a display region where a pixel electrode 19 is present, so that transmission efficiency or reflection efficiency in the display region to light can be improved in addition to the effects. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a display manufacturing method, a display, and an electronic apparatus.

With the thinning of the display, the demand for a large screen area is increasing, and the demand for a large-screen display having a diagonal size of 40 inches is increasing.
In a thin display, for example, a structure for controlling display between flat substrates facing each other, such as a liquid crystal display, is often used. The liquid crystal display performs display using the fact that the polarization state of light transmitted through the liquid crystal differs depending on the orientation of the liquid crystal. Specifically, the alignment of the liquid crystal is controlled by applying a voltage to electrodes provided on opposite surfaces of the substrate having liquid crystal sealed between the substrates. Here, the distance between the opposing substrates is several μm to several tens of μm, and the accuracy is required to be 0.05 μm or less for uniform display.
The distance between the substrates can be determined by a spherical or fiber spacer. However, these spacers are easy to move, and the electrodes, alignment films, and the like provided on the substrate are damaged by the spacers, thereby causing display defects.
In order to solve these problems, a method is known in which column-shaped spacers, so-called column spacers, are formed of resin, and the distance between the substrates is controlled (see, for example, Patent Document 1).

Japanese Patent Laid-Open No. 11-287983 (Section 7, FIG. 4, paragraph number [0037])

  However, when the distance between the substrates is controlled by the column spacer instead of the spherical or fiber-like spacer, a new material and process are required, and the manufacturing efficiency is lowered.

  An object of the present invention is to provide a display manufacturing method, a display, and an electronic apparatus with improved manufacturing efficiency.

  A display manufacturing method according to the present invention is a display manufacturing method including a column spacer for controlling a distance between a switching element substrate and a counter substrate facing the switching element substrate, wherein a bank film is formed on the switching element substrate. Forming a bank film; forming a bank by selectively etching the bank film; forming a column spacer by selectively etching the bank film; And a functional liquid disposing step of disposing in a recess between the banks.

  According to the present invention, since the column spacer is also formed using the bank film in which the bank is formed, new materials and processes are not required, and the manufacturing efficiency is improved.

In the present invention, the column spacer is preferably formed on a region where the switching element is formed.
In the present invention, since the column spacer is formed in the region where the switching element is formed, which is a region different from the display region, the light transmission efficiency in the display region is improved in addition to the above effect.

In the present invention, it is preferable that the functional liquid is disposed at a predetermined position partitioned by the bank to form at least one of the source electrode or the drain electrode.
In this invention, since the bank which partitions the position where the functional liquid for forming at least one of the source electrode and the drain electrode is arranged also serves as the column spacer, the switching element can be formed with high manufacturing efficiency.

  The display of the present invention comprises a switching element substrate having a bank for functional liquid arrangement, a counter substrate facing the switching element substrate, a column spacer between the switching element substrate and the counter substrate, A part of the bank also serves as the column spacer.

  According to the present invention, a display that can achieve the above-described effects can be provided.

In the present invention, the column spacer is preferably formed on a region where the switching element is formed.
The present invention can provide a display that can achieve the above-described effects.

In the present invention, it is preferable that at least one of a source electrode and a drain electrode is formed at a predetermined position partitioned by the bank.
The present invention can provide a display that can achieve the above-described effects.

An electronic apparatus according to the present invention includes the display.
According to the present invention, an electronic device that can achieve the above-described effects can be provided.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
FIG. 1 is a schematic plan view of a liquid crystal display device 100 which is a display in the present embodiment, and FIG. 2 is a schematic cross-sectional view taken along the line HH ′ of FIG.
The liquid crystal display device 100 includes a TFT (Thin Film Transistor) element 30 as a switching element.
In each drawing used for the following description, each layer and each member have different scales so that each layer and each member can be recognized on the drawing.

  1 and 2, the liquid crystal display device 100 includes a TFT array substrate 10 as a switching element substrate on which TFT elements 30 are provided in an array, and a counter substrate 20. These substrates are bonded together by a sealing material 52 which is a photo-curable sealing material. The sealing material 52 is formed in a frame shape between the TFT array substrate 10 and the counter substrate 20. The liquid crystal 50 is sealed and held in a region surrounded by the sealing material 52.

In FIG. 1, a parting 53 made of a light shielding material is formed inside the sealing material 52. An area inside the parting line 53 is an actual image display area 203.
A data line driving circuit 201 and a mounting terminal 202 are formed along one side of the TFT array substrate 10 in a region outside the sealing material 52, and the scanning line driving circuit is formed along two sides adjacent to the one side. 204 is formed. On the remaining side of the TFT array substrate 10, a plurality of wirings 205 for connecting the scanning line driving circuits 204 provided on both sides of the image display area are provided. In addition, an inter-substrate conductive material 206 for providing electrical continuity between the TFT array substrate 10 and the counter electrode 121 provided on the counter substrate 20 is disposed at a corner portion of the counter substrate 20.

Instead of forming the data line driving circuit 201 and the scanning line driving circuit 204 on the TFT array substrate 10, they are formed on the TAB (Tape Automated Bonding) substrate on which the driving LSI is mounted and the peripheral portion of the TFT array substrate 10. The terminal group thus formed may be electrically and mechanically connected via an anisotropic conductive film.
Further, in the liquid crystal display device 100, the phase difference depends on the operation mode, that is, the operation mode such as the TN (Twisted Nematic) mode, the STN (Super Twisted Nematic) mode, or the normally white mode / normally black mode. A plate, a polarizing plate and the like are arranged in a predetermined direction (not shown).

FIG. 3 shows an equivalent circuit diagram of the liquid crystal display device 100.
In the image display area 203 shown in FIG. 1, a plurality of pixels 100A are arranged in a matrix as shown in FIG. 3, and a TFT element 30 is formed in each of these pixels 100A. A data line 6A for sending pixel signals S1, S2,... Sn to the TFT element 30 is electrically connected to the source of the TFT element 30. Pixel signals S1, S2,..., Sn may be sent in this order, or may be sent for each group to a plurality of adjacent data lines 6A. The scanning line 3 </ b> A is electrically connected to the gate of the TFT element 30. The scanning signals G1, G2,..., Gm are applied in this order in a pulsed manner to the scanning line 3A at a predetermined timing.

  The pixel electrode 19 is electrically connected to the drain of the TFT element 30, and by turning on the TFT element 30 for a predetermined time, the pixel signals S1, S2,. Write to the pixel at a predetermined timing. The pixel signals S1, S2,..., Sn written in the liquid crystal 50 through the pixel electrode 19 in this way are held for a certain period of time with the counter electrode 121 shown in FIG. In order to prevent the held pixel signals S1, S2,..., Sn from leaking, a storage capacitor 60 is added in parallel with the liquid crystal capacitor formed between the pixel electrode 19 and the counter electrode 121. For example, the voltage between the pixel electrode 19 and the counter electrode 121 is held by the storage capacitor 60 for a time that is three orders of magnitude longer than the time when the source voltage is applied. Thereby, the charge retention characteristics are improved, and the liquid crystal display device 100 with a high contrast ratio can be realized.

FIG. 4 is a partial enlarged cross-sectional view of the liquid crystal display device 100.
The liquid crystal display device 100 includes a color filter 13 on the counter substrate 20 in order to perform color display. In the region corresponding to each pixel electrode 19 shown in FIG. 3, the color filters of the red filter 13 </ b> A, the green filter 13 </ b> B, and the blue filter 13 </ b> C are formed together with the protective film 18. A black matrix 9 is formed between the red filter 13A, the green filter 13B, and the blue filter 13C.

  A counter electrode 121 is formed on the protective film 18 of the color filter 13, and an alignment film 162 is formed on the counter electrode 121. The opposite surface of the counter substrate 20 on which the color filter 13 is formed is provided with a polarizing plate 175.

  The TFT array substrate 10 includes a transparent glass substrate 170, a TFT element 30 formed on the glass substrate 170, an alignment film 172 formed on the glass substrate 170 and the TFT element 30, and the like. Yes. Further, a surface of the glass substrate 170 opposite to the surface on which the TFT element 30 is formed is provided with a polarizing plate 176.

  The inter-substrate distance between the TFT array substrate 10 and the counter substrate 20 is controlled by a column spacer 67. Here, the column spacer 67 is formed on the region where the TFT element 30 is formed.

  FIG. 5 is an enlarged plan view showing a portion including one TFT element 30 of the TFT array substrate 10. 6A is an enlarged cross-sectional view of the vicinity of the TFT element 30, and FIG. 6B is an enlarged cross-sectional view of a portion where the gate wiring 12 and the source wiring 16 intersect in a plane.

As shown in FIG. 5, on the TFT array substrate 10 having the TFT elements 30, the gate wiring 12, the source wiring 16, the drain electrode 14, the gate electrode 11, and the drain electrode 14 are electrically connected. A pixel electrode 19 and a column spacer 67 are formed.
The gate wiring 12 is formed to extend in the X-axis direction, and a part thereof is formed to extend in the Y-axis direction. A part of the gate wiring 12 extending in the Y-axis direction is used as the gate electrode 11. Note that the width of the gate electrode 11 is narrower than the width of the gate wiring 12. A part of the source wiring 16 formed to extend in the Y-axis direction is formed to extend in the X-axis direction, and a part of the source wiring 16 is used as the source electrode 17.

  As shown in FIGS. 6A and 6B, the gate wiring 12 and the gate electrode 11 are formed between the banks B provided on the glass substrate 170. The gate wiring 12, the gate electrode 11, and the bank B are covered with an insulating film 28 made of SiNx, and an active layer 63 that is a semiconductor layer made of an amorphous silicon (a-Si) layer on the insulating film 28; A source line 16, a source electrode 17, a drain electrode 14, and a bank B1 are formed.

  In FIG. 6A, the active layer 63 is provided substantially at a position facing the gate electrode 11, and a portion of the active layer 63 facing the gate electrode 11 is a channel region. On the active layer 63, bonding layers 64A and 64B made of, for example, n + -type a-Si layers for obtaining an ohmic junction are stacked. The source electrode 17 is connected to the bonding layer 64A, and the drain electrode 14 is connected to the bonding layer. The active layer 63 is joined via 64B. The source electrode 17 and the bonding layer 64A, and the drain electrode 14 and the bonding layer 64B are insulated from each other by a column spacer 67 provided on the active layer 63. The column spacer 67 protrudes in the opposite direction to the glass substrate 170, and controls the inter-substrate distance between the counter substrate 20 shown in FIG.

  6A and 6B, the gate wiring 12 is insulated from the source wiring 16 by the insulating film 28, and the gate electrode 11 is insulated from the source electrode 17 and the drain electrode 14 by the insulating film 28. ing. The source wiring 16, the source electrode 17, and the drain electrode 14 are covered with an insulating film 29. A contact hole is formed in a portion of the insulating film 29 covering the drain electrode 14, and the pixel electrode 19 made of ITO (Indium Tin Oxide) connected to the drain electrode 14 through the contact hole is formed on the upper surface of the insulating film 29. Is formed.

Hereinafter, a process of forming a wiring pattern of the gate wiring 12 of the TFT element 30 will be described.
In the method for forming a wiring pattern in the present embodiment, the bank B is formed on the glass substrate 170 so as to surround the thin film formation region, the wiring pattern forming functional liquid 40 is disposed in the recess surrounded by the bank B, and the glass substrate A wiring film is formed on 170 to form a wiring pattern. Here, the functional liquid 40 can be arranged by a droplet discharge method for discharging droplets.

First, the functional liquid 40 to be used will be described. The functional liquid 40 that is a liquid material is made of a dispersion liquid in which conductive fine particles are dispersed in a dispersion medium. In the present embodiment, as the conductive fine particles, for example, metal oxides containing at least one of gold, silver, copper, aluminum, palladium, and nickel, these oxides, conductive polymers, Superconductor fine particles are used. These conductive fine particles can be used by coating the surface with an organic substance or the like in order to improve dispersibility.
The particle diameter of the conductive fine particles is preferably 1 nm or more and 0.1 μm or less. When the thickness is 1 nm or more, the volume ratio of the coating agent to the conductive fine particles becomes small, and the ratio of the organic matter in the obtained film can be suppressed. Moreover, if it is 0.1 micrometer or less, there is no possibility that clogging will occur in the discharge nozzle of the droplet discharge head used in the droplet discharge method.

  The dispersion medium is not particularly limited as long as it can disperse the conductive fine particles and does not cause aggregation. For example, in addition to water, alcohols such as methanol, ethanol, propanol, butanol, n-heptane, n-octane, decane, dodecane, tetradecane, toluene, xylene, cymene, durene, indene, dipentene, tetrahydronaphthalene, decahydro Hydrocarbon compounds such as naphthalene and cyclohexylbenzene, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol methyl ethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol methyl ethyl ether, 1,2-dimethoxyethane, bis (2- Methoxyethyl) ether, ether compounds such as p-dioxane, propylene carbonate, γ- Butyrolactone, N- methyl-2-pyrrolidone, dimethylformamide, dimethyl sulfoxide, can be exemplified polar compounds such as cyclohexanone. Of these, water, alcohols, hydrocarbon compounds, and ether compounds are preferable and more preferable dispersion media in terms of fine particle dispersibility, dispersion stability, and ease of application to the droplet discharge method. Examples thereof include water and hydrocarbon compounds.

The surface tension of the conductive fine particle dispersion is preferably in the range of 0.02 N / m to 0.07 N / m. When the functional liquid 40 is ejected by the liquid droplet ejection method, if the surface tension is 0.02 N / m or more, the wettability of the functional liquid 40 to the nozzle surface is reduced, and the flying of the liquid droplet is less likely to occur. When the pressure is 0.07 N / m or less, the shape of the meniscus at the nozzle tip is stable, and the discharge amount and discharge timing can be easily controlled.
In order to adjust the surface tension, a small amount of a surface tension regulator such as a fluorine-based, silicone-based, or nonionic-based material may be added to the dispersion within a range that does not significantly reduce the contact angle with the substrate. The nonionic surface tension modifier improves the wettability of the functional liquid 40 to the substrate, improves the leveling property of the film, and helps prevent the occurrence of fine irregularities in the film. The surface tension modifier may contain an organic compound such as alcohol, ether, ester, or ketone, if necessary.

  The viscosity of the dispersion is preferably 1 mPa · s to 50 mPa · s. When discharging the functional liquid as droplets using the droplet discharge method, if the viscosity is 1 mPa · s or more, the nozzle periphery is not easily contaminated by the outflow of the functional liquid, and if the viscosity is 50 mPa · s or less The frequency of clogging in the nozzle holes is reduced, and smooth droplet discharge is facilitated.

FIG. 7 is a flowchart showing an example of a wiring pattern forming method in the present embodiment.
Step S1 is a bank film forming process for forming the bank film 31 for forming the bank B on the glass substrate 170, and the next step S2 is a liquid repellency treatment for imparting liquid repellency to the surface of the bank film 31. The next step S3 is a recess forming process in which the bank B 31 is formed by etching the bank film 31 in accordance with the pattern shape of the gate wiring 12. Further, the next step S4 is a functional liquid disposing step of disposing the functional liquid 40 in the recesses between the banks B to which liquid repellency is imparted, and the next step S5 is at least a part of the liquid components of the functional liquid 40. Step S6 is a baking step in which heat treatment is performed to obtain conductivity when the conductive fine particles contained in the functional liquid 40 are organic silver compounds.

Hereinafter, the formation process of the gate wiring 12 will be described in detail for each step.
FIG. 8 is a schematic cross-sectional view showing an example of a procedure for forming the gate wiring 12.
First, the bank film forming process in step S1 will be described.
In FIG. 8A, before the formation material of the bank film 31 is applied, the glass substrate 170 is subjected to HMDS treatment as a surface modification treatment. The HMDS treatment is a treatment in which hexamethyldisilazane ((CH ₃ ) ₃ SiNHSi (CH ₃ ) ₃ ) is applied in a vapor state. Thereby, the HMDS layer 32 which is an adhesion layer for improving the adhesion between the bank film 31 and the glass substrate 170 is formed on the glass substrate 170.

The bank B formed from the bank film 31 is a member that functions as a partition member, and the bank B can be formed by any method such as a photolithography method or a printing method. For example, when the photolithography method is used, the material for forming the bank film 31 is applied by a predetermined method such as spin coating, spray coating, roll coating, die coating, dip coating, or the like.
A material for forming the bank film 31 is applied on the HMDS layer 32 of the glass substrate 170 in accordance with the height of the bank B, thereby forming the bank film 31 shown in FIG.

  As a material for forming the bank film 31, a material having lyophilicity with respect to the functional liquid 40 is used. Examples of the material having lyophilicity with respect to the functional liquid 40 include, for example, polysilazane, polysiloxane, siloxane-based resist, polysilane-based resist and the like, a polymer inorganic material containing silicon in the skeleton, a photosensitive inorganic material, silica glass, alkyl Examples thereof include a siloxane polymer, an alkyl silsesquioxane polymer, a hydrogenated alkyl silsesquioxane polymer, a spin-on-glass film containing any of polyaryl ethers, a diamond film, and a fluorinated amorphous carbon film. Furthermore, as a material for forming the bank film 31 having lyophilicity with respect to the functional liquid 40, for example, airgel, porous silica, or the like may be used.

  Further, an organic material can be used as a material for forming the bank film 31. For example, a polymer material such as an acrylic resin, a polyimide resin, an olefin resin, a phenol resin, or a melamine resin can be used.

  The degree of lyophilicity of the material for forming the bank film 31 is preferably such that the contact angle of the functional liquid 40 with respect to the bank film 31 is less than 40 °. If the contact angle of the functional liquid with respect to the bank film 31 is less than 40 °, the side surface 36 of the concave portion 34 described later has a contact angle with respect to the functional liquid 40 of less than 40 °, and the dropped functional liquid 40 easily spreads into the concave portion 34. Become.

Next, the lyophobic treatment process in step S2 will be described. In the liquid repellency treatment step, the bank film 31 is subjected to a liquid repellency treatment to impart liquid repellency to the surface. As the liquid repellent treatment, a plasma treatment method (CF ₄ plasma treatment method) using carbon tetrafluoride (tetrafluoromethane) as a treatment gas is employed. The conditions of the CF ₄ plasma treatment are, for example, a plasma power of 50 to 1000 W, a carbon tetrafluoride gas flow rate of 50 to 100 mL / min, a substrate transport speed to the plasma discharge electrode of 0.5 to 1020 mm / sec, and a substrate temperature of 70 to 90 ° C. The processing gas is not limited to tetrafluoromethane, and other fluorocarbon-based gases or gases such as SF ₆ and SF ₅ CF ₃ can also be used.

  By performing such a liquid repellent treatment, as shown in FIG. 8B, a liquid repellent treatment layer 37 in which fluorine groups are introduced into the resin constituting the bank film 31 is formed on the surface of the bank film 31. Thus, high liquid repellency is imparted to the functional liquid. The degree of liquid repellency of the liquid repellent treatment layer 37 is preferably such that the contact angle of the functional liquid 40 is 40 ° or more. When the contact angle is 40 ° or more, the functional liquid 40 hardly remains on the upper surface of the bank B. Therefore, the dropped functional liquid 40 is likely to enter the recess 34 described later from the upper surface of the bank B.

  Next, the recess forming step in step S3 will be described. In the recess forming step, a part of the bank film 31 is removed by using a photolithography method, and the recess 34 surrounded by the bank B is formed. First, a resist layer is applied on the bank film 31 formed in the bank film forming process of step S1. Next, by applying a mask according to the bank shape (wiring pattern shape) and exposing / developing the resist layer, a resist 38 according to the shape of the bank B is formed as shown in FIG. Finally, etching is performed to remove the bank film 31 other than the portion covered with the resist 38, and the remaining resist 38 is removed.

  Next, after the bank B is formed on the glass substrate 170, hydrofluoric acid treatment is performed. The hydrofluoric acid treatment is a process of removing the HMDS layer 32 between the banks B by etching with, for example, a 2.5% hydrofluoric acid aqueous solution. In the hydrofluoric acid treatment, the bank B functions as a mask, and as shown in FIG. 8D, the organic HMDS layer 32 at the bottom 35 of the recess 34 formed between the banks B is removed, and the glass substrate 170 is removed. Is exposed. Glass or quartz glass used as the glass substrate 170 on which the wiring pattern is formed has lyophilicity with respect to the functional liquid 40, and the bottom portion 35 where the glass substrate 170 is exposed is close to the functional liquid 40. Become liquid.

  As a result, as shown in FIG. 8D, the recess 34 surrounded by the bank B is formed, and the recess formation step of step S3 is completed. The liquid repellent treatment layer 37 formed in the above-described liquid repellency treatment step is formed on the upper surface of the bank B formed in the recess formation step, and the upper surface of the bank B repels the functional liquid 40. It is liquid. In contrast, the side surface 36 of the bank B is lyophilic with respect to the functional liquid 40 because the forming material of the bank film 31 having lyophilicity is directly exposed to the functional liquid 40. . As described above, the bottom portion 35 is lyophilic with respect to the functional liquid 40, and the concave portion 34 includes the lyophilic side surface 36 and the bottom portion 35.

Next, the functional liquid arrangement process in step S4 will be described.
In the functional liquid disposing step, the liquid droplets of the functional liquid 40 for forming the wiring pattern are disposed in the recesses 34 between the banks B on the glass substrate 170 using a liquid droplet ejecting method using a liquid droplet ejecting apparatus. Here, a functional liquid 40 made of an organic silver compound using an organic silver compound as a conductive material and diethylene glycol diethyl ether as a solvent (dispersion medium) is discharged. The functional liquid 40 is disposed in the recesses 34 by discharging droplets of the functional liquid 40 toward the recesses 34 between the banks B. At this time, as shown in FIG. 8E, the wiring pattern formation scheduled region (that is, the recess 34) from which the droplet is ejected is surrounded by the bank B, so that the droplet can be prevented from spreading to other than the predetermined position. .

Next, the intermediate drying process of step S5 will be described.
After the droplets are discharged onto the glass substrate 170, a drying process is performed as necessary in order to remove the dispersion medium of the functional liquid 40 and ensure the film thickness. The drying process can be performed by lamp annealing, for example, in addition to a process using a normal hot plate or an electric furnace for heating the glass substrate 170. The light source used for lamp annealing is not particularly limited, but excimer lasers such as infrared lamps, xenon lamps, YAG lasers, argon lasers, carbon dioxide lasers, XeF, XeCl, XeBr, KrF, KrCl, ArF, ArCl, etc. It can be used as a light source. These light sources generally have a power output in the range of 10 W to 5000 W, but in the present embodiment, a range of 100 W to 1000 W is sufficient.
When the intermediate drying process is completed, the gate wiring 12 and the gate electrode 11 are formed as shown in FIG.

  Next, the firing process in step S6 will be described. In the case of an organic silver compound, the dried film after the intermediate drying step needs to be heat-treated in order to obtain conductivity, to remove organic components of the organic silver compound and to leave silver particles. For this reason, the substrate after the discharge process is subjected to heat treatment and / or light treatment.

  The heat treatment and / or light treatment is usually performed in the air, but can be performed in an inert gas atmosphere such as nitrogen, argon or helium, or in a reducing atmosphere such as hydrogen, if necessary. The treatment temperature of heat treatment and / or light treatment depends on the boiling point (vapor pressure) of the dispersion medium, the type and pressure of the atmospheric gas, the thermal behavior such as fine particle dispersibility and oxidation, the presence and amount of coating material, It is determined appropriately in consideration of the heat resistant temperature. In the present embodiment, a firing process is performed for 300 minutes at 280 to 300 ° C. in a clean oven in the atmosphere for the functional liquid 40 that has been ejected to form a pattern. For example, in order to remove the organic component of the organic silver compound, it is necessary to bake at about 200 ° C. In the case of using a substrate made of plastic or the like, it is preferably performed at room temperature or higher and 250 ° C. or lower. Through the above steps, the dry film after the discharging process is converted into a conductive film while ensuring electrical contact between the fine particles.

Below, the manufacturing method of the TFT element 30 and the column spacer 67 is demonstrated based on drawing.
FIG. 9 is a flowchart showing a method for manufacturing the TFT element 30 and the column spacer 67.
Step S21 is an active layer forming process for forming the active layer 63, which is a semiconductor layer, and the next step S22 is a bank film forming process for forming the bank film 71 for forming the bank B1 and the like. The next step S <b> 23 is a spacer forming process for forming the column spacer 67 from the bank film 71. The next step S24 is a liquid repellency treatment process for imparting liquid repellency to the surface of the bank film 71, and the next step S25 is to etch the bank film 71 so as to form a recess 74 corresponding to the shape of the wiring pattern. It is the recessed part formation process to do. The next step S26 is a functional liquid placement step in which the functional liquid 81 is placed in the recess 74 between the banks B1 to which liquid repellency is imparted. In the next step S27, at least part of the liquid components of the functional liquid 81 is removed. This is an intermediate drying step to be removed, and the next step S28 is a firing step in which heat treatment is performed to obtain conductivity when the conductive fine particles contained in the functional liquid 81 are organic silver compounds.

Hereafter, it demonstrates in detail for every process of each step.
FIG. 10 shows from the active layer forming step to the column spacer forming step, and FIG. 11 shows from the liquid repellent treatment step to the recess forming step. FIG. 12 shows the process from the functional liquid placement process to the firing process, and FIG. 13 shows the process from the completion of the liquid crystal display device 100 to the completion of the process.

As shown in FIG. 10A, in the active layer forming step of step S21, the insulating film 28 as a gate insulating film, the active layer 63 as a semiconductor layer, and the bonding layer 64 are continuously formed by plasma CVD.
A silicon nitride film is formed as the insulating film 28, an amorphous silicon film is formed as the active layer 63, and an n + type silicon film is formed as the bonding layer 64 by changing the source gas and plasma conditions. When formed by a CVD method, a heat history of 300 ° C. to 350 ° C. is required, but a silica glass-based material containing silicon as a main component in the main chain of the basic skeleton and a structure such as hydrocarbon in the side chain Can be used in a bank to avoid problems with transparency and heat resistance.
Next, the bonding layer 64 is etched to be separated into a bonding layer 64A bonded to the source electrode 17 and a bonding layer 64B bonded to the drain electrode 14.

Next, the bank film forming process in step S22 will be described.
The banks B1 and B2 formed from the bank film 71 can be formed by the same method as the bank B. A bank film 71 is formed on the insulating film 28 at a height that can cover the active layer 63 and the bonding layer 64 to form the bank film 71 as shown in FIG.

  In the bank film forming step, a material having lyophilicity with respect to the functional liquid 81 is used as a material for forming the bank film 71, but it also serves as a material for forming the column spacer 67, so The organic materials described above that can absorb impact are preferred. The degree of lyophilicity of the bank forming material is preferably such that the contact angle of the functional liquid 81 is less than 40 °. When the contact angle is 40 ° or more, the lyophilic property may not be sufficient depending on the shape of a recess 74 (see FIG. 11E) described later.

Next, the column spacer forming process in step S23 will be described.
A resist 78 is formed in a region on the bank film 71 corresponding to between the bonding layers 64A and 64B. Thereafter, the bank film 71 is etched by photolithography to form column spacers 67. The column spacer 67 is formed to have a height corresponding to the distance between the TFT array substrate 10 and the counter substrate 20. Therefore, etching is performed until the column spacer 67 reaches the height (see FIG. 10C). Here, the planar shape of the resist 78 is the cross-sectional shape of the column spacer 67. In the present embodiment, the planar shape of the resist 78 is a circle (see FIG. 5).

  Next, the liquid repellency process in step S24 will be described. In the liquid repellency treatment step, the bank film 71 is subjected to a liquid repellency treatment to impart liquid repellency to the surface. As the liquid repellent treatment, the above-described method can be used.

  By performing such a liquid repellent treatment, as shown in FIG. 10C, a liquid repellent treatment layer 77 in which a fluorine group is introduced into the resin constituting the bank film 71 is formed on the surface of the bank film 71. Thus, high liquid repellency is imparted to the functional liquid 81. The degree of liquid repellency of the liquid repellent treatment layer 77 is preferably such that the contact angle of the functional liquid 81 is 40 ° or more.

Next, the recess forming step in step S25 will be described.
In the recess formation step, a part of the bank film 71 is removed by using a photolithography method, and the recesses 74 surrounded by the banks B1 and B2 and the banks B1 and B2 are formed.
First, a resist layer is applied on the bank film 71 on which the column spacer 67 is formed. Next, by applying a mask in accordance with the bank shape (wiring pattern shape) and exposing / developing the resist, as shown in FIG. 11D, a resist 78 that matches the top of the column spacer 67 and the bank shape is formed. leave. Thereafter, etching is performed. Finally, the resist 78 is removed.

  Thereby, as shown in FIG. 11E, the recess 74 surrounded by the bank B1 and the bank B2 is formed, and the recess forming step of step S25 is completed. A liquid repellent treatment layer 77 formed in the liquid repellency treatment process is formed on the upper surfaces of the banks B1 and B2 formed in the recess formation process, and the upper surfaces of the banks B1 and B2 are in contact with the functional liquid. It is liquid repellent. In contrast, the side surface 76 of the bank B1 is lyophilic with respect to the functional liquid 81 because the forming material of the bank film 71 having lyophilicity is directly exposed to the functional liquid. Similarly, the side surface 79 of the bank B <b> 2 is lyophilic with respect to the functional liquid 81 because the forming material of the bank film 71 having lyophilicity is directly exposed to the functional liquid 81. The bottom surface 75, the active layer 63, and the bonding layers 64A and 64B, which are the surfaces of the insulating film 28, are lyophilic with respect to the functional liquid, and the recess 74 has the lyophilic side surfaces 76 and 79, the active layer. 63, a bonding layer 64, and a bottom surface 75.

Next, the functional liquid arrangement process in step S26 will be described.
In FIG. 12A, in the functional liquid disposing process, the liquid droplets of the wiring pattern forming functional liquid 81 are disposed in the recesses 74 formed in the banks B1 and B2 by using a droplet discharge method. Here, a functional liquid 81 made of an organic silver compound using an organic silver compound as a conductive material and diethylene glycol diethyl ether as a dispersion medium is discharged. In the functional liquid arranging step, the functional liquid 81 is arranged in the concave portion 74 by discharging a droplet of the functional liquid 81 toward the concave portion 74. At this time, since the wiring pattern formation scheduled region (that is, the recess 74) from which the droplet is discharged is surrounded by the banks B1 and B2, it is possible to prevent the droplet from spreading outside the predetermined position.

  The width of the recess 74 (here, the width at the opening of the recess 74) is set to be approximately equal to the diameter of the droplet of the functional liquid 81. Note that the atmosphere for discharging the droplets is preferably set to a temperature of 60 ° C. or lower and a humidity of 80% or lower. Thereby, stable droplet discharge can be performed without clogging the discharge nozzle.

  Further, the functional liquid 81 discharged into the recess 74 or flowing down from the surfaces of the banks B1 and B2 is easy to spread because the bottom surface 75 and the side surface 76 are lyophilic, and thus the functional liquid 81 is more The recess 74 is uniformly filled.

Next, the intermediate drying process of step S27 will be described.
In order to remove the dispersion medium of the functional liquid 81 and ensure the film thickness, a drying process is performed as necessary. The intermediate drying process in step S27 is basically the same as the intermediate drying process in step S5. By the intermediate drying process in step S27, as shown in FIG. 12B, a circuit wiring film 73, which is a wiring film for forming a wiring pattern, is formed. In the present embodiment, the wiring pattern formed by the circuit wiring film 73 is the source wiring 16, the source electrode 17, and the drain electrode 14 shown in FIGS. 5 and 6.

  When the thickness of the circuit wiring film 73 that can be formed by one functional liquid arranging step and the intermediate drying step does not reach a required film thickness, the intermediate drying step and the functional liquid arranging step are repeated. It should be noted that the number of repetitions of repeating the intermediate drying step and the functional liquid disposing step is appropriately determined from the thickness of the circuit wiring film 73 that can be formed by one functional liquid disposing step and the intermediate drying step and the required film thickness. The required film thickness can be obtained. Further, different functional liquids 81 may be laminated as necessary.

Next, the firing process in step S28 will be described.
In the case of an organic silver compound, the dried film after the intermediate drying step needs to be heat-treated in order to obtain conductivity, to remove organic components of the organic silver compound and to leave silver particles. For this reason, the substrate after the discharge process is subjected to heat treatment and / or light treatment.

  The firing process in step S28 is basically the same as the firing process in step S6 described above. By the baking process of step S28, the dry film ensures electrical contact between the fine particles and is converted into a conductive film. Through the above steps, the dry film after the discharging process is converted into a conductive film while ensuring electrical contact between the fine particles.

Below, the formation process of the liquid crystal display device 100 is demonstrated.
In FIG. 13C, after removing the liquid repellent layer 77, an insulating film 29 is formed so as to fill the recess 74 in which the source electrode 17 and the drain electrode 14 are disposed.
Next, a contact hole is formed in a portion of the insulating film 29 covering the drain electrode 14, and a patterned pixel electrode 19 is formed on the upper surface, and the drain electrode 14 and the pixel electrode 19 are connected via the contact hole. .

  Finally, after forming the alignment film 172 on the TFT array substrate 10, the counter substrate 20 is combined and the liquid crystal 50 is sealed. Then, the liquid crystal display device 100 shown in FIG. 13D is obtained by bonding the polarizing plates 175 and 176, respectively.

According to this embodiment, there are the following effects.
(1) Since the column spacer 67 can also be formed using the bank film 71 on which the banks B1 and B2 are formed, new materials and processes are not required, and the manufacturing efficiency can be improved.

  (2) Since the column spacer 67 can be formed in a region where the TFT element 30 is formed, which is different from the display region where the pixel electrode 19 exists, in addition to the above-described effects, light transmission efficiency or reflection efficiency in the display region Can be improved.

  (3) Since the column spacer 67 also serves as the bank B2 for partitioning the position where the functional liquid 81 that forms at least one of the source electrode 17 and the drain electrode 14 is disposed, the switching element can be formed with high manufacturing efficiency.

  (4) The liquid crystal display device 100 that can achieve the above-described effects can be provided.

(Second Embodiment)
Next, an electronic apparatus according to the present invention will be described based on a second embodiment.
The electronic device of the present embodiment is an electronic device including the liquid crystal display device 100 described in the first embodiment. A specific example of the electronic apparatus of this embodiment will be described.

  FIG. 14A is a perspective view illustrating an example of a mobile phone 600 that is an example of an electronic apparatus. 14A, a mobile phone 600 includes a liquid crystal display unit 601 in which the liquid crystal display device 100 of the first embodiment is incorporated.

  FIG. 14B is a perspective view showing an example of a portable information processing apparatus 700 such as a word processor or a personal computer. 14B, a portable information processing device 700 includes an input unit such as a keyboard 701, an information processing body 703, and a liquid crystal display unit 702 in which the liquid crystal display device 100 of the first embodiment is incorporated.

  FIG. 14C is a perspective view showing an example of a wrist watch type electronic apparatus 800. In FIG. 14C, the wristwatch type electronic device 800 includes a liquid crystal display unit 801 in which the liquid crystal display device 100 of the first embodiment is incorporated.

  FIG. 14D is a perspective view showing a large liquid crystal TV 900. 14D, the large liquid crystal TV 900 includes a liquid crystal display unit 901 in which the liquid crystal display device 100 of the first embodiment is incorporated.

According to the second embodiment, the following effects can be obtained.
(5) A mobile phone 600, a portable information processing device 700, a wristwatch-type electronic device 800, and a large liquid crystal TV 900, which are electronic devices that can achieve the above-described effects, can be provided.

It should be noted that the present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention.
For example, in the above embodiment, the bank film 71 is etched and the column spacer 67 is provided on the region where the TFT element 30 is formed, but the bank film 31 is etched and provided on the region where the black matrix 9 is formed. Also good.

The best method for carrying out the present invention has been disclosed in the above description, but the present invention is not limited to this. That is, the present invention has been described mainly with reference to specific embodiments, but without departing from the scope of the technical idea and object of the present invention, the materials, processing time, Various other modifications can be made by those skilled in the art.
Accordingly, the descriptions of the materials disclosed above, the processing time, and the like are limited to those described for illustrative purposes in order to facilitate understanding of the present invention and are not intended to limit the present invention. Descriptions excluding some or all of the limitations such as processing time are included in the present invention.

1 is a schematic plan view of a liquid crystal display device according to a first embodiment. 1 is a schematic cross-sectional view of a liquid crystal display device. The equivalent circuit diagram of a liquid crystal display device. The partial expanded sectional view of a liquid crystal display device. The enlarged plan view which showed the part containing the TFT element of a TFT array substrate. (A) is an enlarged sectional view of a TFT element, and (b) is a partially enlarged sectional view in which a gate wiring and a source wiring intersect in a plane. The flowchart which shows the formation method of a wiring pattern. FIG. 6 is a schematic cross-sectional view showing a procedure for forming a gate wiring. The flowchart which shows the formation method of a TFT element part. The schematic cross section which shows from an active layer formation process to a column spacer formation process. The schematic cross section which shows from a liquid-repellent treatment process to a recessed part formation process. The schematic cross section which shows from a functional liquid arrangement | positioning process to a baking process. FIG. 6 is a schematic cross-sectional view showing a process until a liquid crystal display device is completed. The figure which shows the electronic device in 2nd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... FTF array board | substrate as a switching element board | substrate, 20 ... Opposite board | substrate, 67 ... Column spacer, 100 ... Liquid crystal display device as a display, 31, 71 ... Bank film | membrane, B, B1, B2 ... Bank, 40, 81 ... Function Liquid, 30 ... TFT elements as switching elements, 34, 74 ... concave portions.

Claims (7)

A method for manufacturing a display including a column spacer for controlling a distance between a switching element substrate and a counter substrate facing the switching element substrate,
A bank film forming step of forming a bank film on the switching element substrate;
A recess forming step of selectively etching the bank film to form a bank;
A spacer forming step of selectively etching the bank film to form the column spacer;
And a functional liquid disposing step of disposing the functional liquid in the recesses between the banks. In the manufacturing method of the display of Claim 1,
The column spacer is formed on a region where a switching element is formed. A method for manufacturing a display. In the manufacturing method of the display of Claim 1 or Claim 2,
A method of manufacturing a display, comprising: disposing a functional liquid at a predetermined position partitioned by the bank to form at least one of a source electrode and a drain electrode. A switching element substrate having a bank for functional liquid arrangement;
A counter substrate facing the switching element substrate;
A column spacer is provided between the switching element substrate and the counter substrate,
A part of the bank also serves as the column spacer. The display according to claim 4, wherein
The column spacer is formed on a region where the switching element is formed. The display according to claim 4 or claim 5,
A display having at least one of a source electrode and a drain electrode formed at a predetermined position partitioned by the bank. An electronic device comprising the display according to claim 4.

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